blueorison wrote:Heavier grains = more impact/energy on target. For target shooting, it is generally more accurate and your bullet is more stable in flight. That's the short version. As long as you have the right twist (you do), you can use heavier grain such as 77gr, 80gr, 90gr, and 100gr (I'd recommend a 6.+ twist for the 100gr, but 1:7 will handle it fine).
Gotcha. Thanks. So at what range will one notice an accuracy difference? From 25 yards and beyond, or do you have to be shooting 100 yards or more to see increased accuracy? Until I get the 3X FTS magnifier for my FS2000, I'll only be shooting 25 to 75 yards. When I upgrade to 100 yards, would I see an accuracy improvement going from using 55gr to 77gr?
Like I said, that was the highly condensed answer
At 25-75 yards, you can use the worst factory ammunition and you wont get more than a 1-2 inch deviation from the X you're aiming at.
There are many variables and factors that go into rounds. I'm assuming you're dealing with factory rounds, so that makes it easier to discuss. Good handloads, however, will outperform ANY factory ammunition you buy. So you might want to look into reloading. The way the brass is prepped, the quality and brand of brass used, the powder used, the bullet, the reloading equipment, seating depth of the bullet, crimps, cannelures, primers, etc. all factor into the accuracy of the round downrange.
However, with factory ammunition, this is not your concern per se, as they have been loaded for you and you cannot modify (see: should not modify...) factory ammunition for 5.56/.223.
Just because the round is heavier, does not mean it is a definite candidate for higher accuracy. As I always mandate, correlation does not imply causation. If you buy wolf 75gr, PMC 55gr will still be more accurate than the heavier round. This is because the quality of the wolf 75gr is considerably crap compared to PMC's quality. So the fact that a heavier grain bullet has a better sustained flight path in general doesn't always mean it is more accurate than a lighter grain. One way to understand this is that if any factory loaded a 75gr and 55gr with the correct powder ratios using the same primer and casing specs, the 75 gr will most likely be more accurate at longer distances. However, different mfg's use different brass, powders, etc.
However, most manufacturers WILL reserve the higher grain bullets (which are more expensive) for better quality ammunition that is "match" accurate; that is, more accurate than normal "plinking" ammunition. Thus, heavier grains does usually correlate to match and more accurate rounds. The term "match" doesn't always mean you're getting accurate ammunition, many mfg's just use it as a term to sell their relabeled crap.
I've shot every factory round you can find in the stores, and even those that you can't. I actually just spent a year and hundreds of dollars testing ammunition for the 5.56. If you have any other questions, feel free to ask and I'll do my best to answer them concisely and succinctly.
At this point, shooting at 75 yards, I wouldn't worry about purchasing match ammunition, just shoot what is cheapest and more economical and get your shooting skill level up to where it needs to be for that 100-300yard shot i the future
When you do get a chance to shoot 100-300yds, send me a PM and I'll recommend you some good ammunition.
Hope that has cleared things up.